Electrolytic diaphragm cells including current connection means between the cell base and anode

ABSTRACT

Electrolytic diaphragm cells are provided comprising a plurality of vertical substantially flat and hollow anodes formed, as regards at least one of their two substantially parallel faces, by a sheet of a film-forming metal, said anodes being secured to the base of the cell by means of extended portions which pass through the base, characterized in that the extended portions comprise a core made of a metal which is a good electrical conductor, which core is covered by a sheath made of a filmforming metal, a good electrical contact being ensured between the sheath and the core. The core of the extended portions is exposed where it passes through the base of the cell, with the electrical connection between the base and the core comprising resilient metal parts arranged between the core and the base.

United States Patent Bouy et al.

[75] Inventors: Pierre Bouy, Enghien-les-Bains;

Daniel Masure, La Madeleine; Paul Collon, Autreville; Jean-MariePigeaud, Martigues; Bernard Sartre, Levallois-Perret, all of France [73]Assignee: Rhone-Progil, Paris, France [22] Filed: Dec. 19,1972

[2!] Appl. No: 316,515

{30] Foreign Application Priority Data Dec. 23, 1971 France 71.46296[52] US. Cl. 204/263; 204/252; 204/266; 204/286; 204/290 F [51] Int. ClB0lk 3/10 [58] Field of Search 204/252, 266, 286, 290 F, 204/263 [56]References Cited UNITED STATES PATENTS 3,515,661 6/1970 Coulter 204/2863,591,483 7/1971 Loftfield et al. l. 204/252 June 24, 1975 3,632,4971/1972 Leduc 204/266 OTHER PUBLICATIONS Cotton, J. B., Platinum-facedTitanium for Electrochemical Anodes, ln Platinum Metals Review, 2(2):pp. 4547, April, 1958.

Primary Examiner.l0hn H. Mack Assistant Examiner-W. 1. Solomon [57]ABSTRACT Electrolytic diaphragm cells are provided comprising aplurality of vertical substantially flat and hollow anodes formed, asregards at least one of their two substantially parallel faces, by asheet of a film-forming metal, said anodes being secured to the base ofthe cell by means of extended portions which pass through the base,characterized in that the extended portions comprise a core made of ametal which is a good electrical conductor, which core is covered by asheath made of a film-forming metal, a good electrical contact beingensured between the sheath and the core. The core of the extendedportions is exposed where it passes through the base of the cell. withthe electrical connection between the base and the core comprisingresilient metal parts arranged between the core and the base.

4 Claims, 4 Drawing Figures PATENTEI] JUN 24 I975 SHEET K VI, V

ELECTROLYTIC DIAPHRAGM CELLS INCLUDING CURRENT CONNECTION MEANS BETWEENTHE CELL BASE AND ANODE BACKGROUND OF THE INVENTION The presentinvention relates to electrolytic diaphragm cells provided with flat andhollow metal anodes which are formed, at least as regards one of theirtwo parallel faces, by an apertured sheet or a lattice made of titaniumor a metal or alloy having similar anodic properties. The anodes arealso provided with extended portions for the input of electric currentand for fixing the anodes to the bases of the cells.

The advantages are known of using titanium or metals or alloys havingsimilar properties instead of graphite anodes in electrolytic cells,with such anodes being covered with a conducting metal which is notattacked by the electrolytic solutions. In particular, French Pat. No.1,600,249 describes constructions in which such metal anodes areextended by metal portions for securing them to the base of the cells,and for the input of the electrical current.

It is an object of the present invention to provide electrolyticdiaphragm cells having improved anodes.

It is also an object of the present invention to provide electrolyticdiaphragm cells having anodes which permit a more favorable distributionof electrical current.

These and other objects will be apparent to those skilled in the artfrom the present description, taken in conjunction with the appendeddrawings, in which:

FIG. I is an elevational view of an anode of the invention.

FIG. 2 is an elevational view of the lower part of the anode of FIG. 1having an extended portion fastened to the base of a cell.

FIG. 3 is an elevational view of another anode extended portion fastenedto the base of a cell.

FIG. 4 is an elevational view of the lower part of an anode extendedportion fastened to the base of the cell, with the electrical connectionto the core portion shown.

GENERAL DESCRIPTION OF THE INVENTION The improved constructions nowdescribed of the present invention use extended portions comprising acore made of a material which is a good electrical conductor, the corebeing covered with a sheath of titanium or other film-forming metal oralloy having similar anodic properties, so that a perfect electricalconnection is ensured between the sheath and the core. The use of suchextended portions makes it possible to achieve a reduction in the dropsin potential, by supplying current directly to the core of the extendedportions, the active parts which are the flat faces of the anodesthemselves being welded to the sheath of the extended portions.Moreover, and advantageously, the extended portions can extend in spacebetween the two parallel faces of the anodes, as far as their upperpart, and can be welded to the faces of the anodes in such a way thatthe most favourable distribution of the electrical current is ensured atthat point.

In practice, depending on the dimensions of the anodes and theirelectrical characteristics, one or more of such extended portions isused per anode, the use of a single extended portion enjoying theadvantage, however, that it is not subjected to forces due to expansionof the elements of the anode. Extended portions of this nature arepreferably made from jointly drawn members which are cylindrical inshape. It is easy to see that such a cylindrical shape permits variousmachining operations for ensuring a current feed to the extendedportions.

A first way in which electrical current can be supplied comprisesexposing the conducting core of the extended portion at its lower endwhich passes through the base of the cell. This permits securing to thecore in various known manners the current supply leads. It also providesfor a screw-thread on the sheath where it passes through the base, andsecuring thereto by welding above the screw-thread a washer of the sameor a similar metal, and thus to tighten the extended portions to thecell base. Also provided is sealing by means of a sealing gasket, whichis preferably toric or toroidal, interposed between the washer and thebase. The current supply leads can be secured to the base of the celland, if the base is metal, they can then act as a general current inputfor the anodes.

Another way in which the electrical current can be supplied to theextended portions of the anode in the case where the base of the cell isof metal, comprises gripping the conducting core of the extendedportions of the anode, which is bared or exposed where it passes throughthe base of the cell, by the metal of which the base itself is made.This gripping effect can be achieved by simply making the core have aforce or frictional fit in the base. However, it is preferably achievedby shrink-fitting, by establishing before assembly a sufficienttemperature difference between the base and the extended portions of theanode, for example, by immersing the latter in liquid nitrogen beforefitting. Upon expansion where returning to atmospheric or elevatedtemperature, a tight fit is possible. Dismantling, if required, can beeffected by various means which can be used in combination, and whichcan include (1) screw extractors, (2) by providing the variousanchorages required, (3) conical machining of the core of the extendedportions, (4) passages provided in the core so that a cooling fluid canbe circulated therein, and (5) means for heating the base. In thissecond way of feeding the electrode with current, it is obvious thatsealing can be effected in a smilar manner to that described above, bysquashing, when the anodes are assembled, a sealing gasket comprising asuitable elastomer, precisely by the amount required, between a washersecured to the extended portions and the base of the cell. Also, thismay be accomplished by clamping the joint after assembly against thebase by means of a washer which is screwed on to the sheath of theextended portions. It is also possible to effect sealing by welding onby means of their edges thin pieces of titanium or other film-formingmetal, replacing the washers used hereinbefore, for protecting the baseof the cell with titanium.

A third way in which the current supply can be provided, comprises usinga conducting metal for making the base of the cell and making aconnection between the base and the extended portions by means ofresilient contacts arranged in an annular space provided between theconducting core of the extended portions, which core is bared where itpasses through the base, and the aperture through which it passesthrough the base, sealing being effected in the same manner ashereinbefore, by means of sealing gaskets.

SPECIFIC DESCRIPTION OF THE INVENTION Embodiments of the presentinvention will be described by way of example hereinafter with referenceto the accompanying drawings.

FIG. 1 shows an elevational view of an anode according to the inventioncomprising two expanded or apertured sheets I of titanium or otherfilm-forming metal, such as tantalum, tungsten, zirconium, etc. Theseare welded along their vertical axes to the tianium sheath of acylindrical jointly-drawn member 2 comprising copper and titanium. Thetitanium sheets 1 may be in the form of a lattice. Threaded on to andwelded to the lower part of the member 2 is a washer 3 comprisingtitanium or other film-forming metal, which, by way of the toric sealinggasket 4, provides for sealing with respect to the polyester base 5 ofthe electrolytic cell. The titanium sheath of the part of the member 2which is located below the washer 3 is screw-threaded so that the anodecan be tightened to the base of the cell by means of a nut 6. The coppercore 7 of the lower end of the member 2 is bared or exposed and carriesa sleeve 8 connected by a bunch 9 of copper wires to the electriccurrent supply rod 10. The vertical edges of the titanium sheets I areconnected by welding by means of members which are also made of expandedtitanium sheets.

FIG. 2. shows an elevational view of the lower part of an anodeaccording to the invention having its extended portion which is grippedin the base of the cell, the anode itself being made as describedhereinbefore with reference to FIG. I. The extended portion 11 is acylindrical jointly drawn member comprising copper and titanium. Thecopper core of the lower part of the copper-titanium member is exposedat 12 over a height corresponding to the thickness of the base of thecell, the base being preferably made of cast aluminum and indicated byreference 13. A passage 14 in the copper core permits the temperature ofthe member to be reduced by circulating liquid nitrogen therein, so thatassembly and dismantling can be effected by shrinkfitting as describedhereinabove, the machining tolerances of the copper core and the bore ofthe corresponding hole in the base of the cell being gauged inconsequence.

Protection from corrosion is effected in the following manner; the base13 of the cell is covered by a titanium sheet 15 in which are providedcircular apertures coaxial with the electrode extended portions. Theedge of the apertures is relieved at 16; a washer-shaped member 17provided with a relieved edge 18 and made from a titanium sheet of thesame thickness as the titanium sheet 15 is welded at 19 to the sheath 20of the member 11, and the edges 16 and 18 are welded at 21. The weldingcan be ground off before dismantling the anode.

FIG. 3 also shows another mode of gripping an anode extended portion ofan anode of the invention in the base of the cell. This Figure againshows the cylindrical copper-titanium member 11, the sheath 20 of themember 11, the copper core exposed at 12 at the lower end of the member11, and the cooling passage 14. In this construction, the base 13 of thecell is covered with a titanium sheet 22 provided with circularapertures through which the extended portions pass. Welded to the sheath20 is a titanium washer 23 for scaling to the base by means of a toricseal 24 which is crushed or flattened during assembly.

Flg. 4 shows and elevational view of the lower part of an anode extendedportion, and the means for electrical connection between the core of theextended portion and the metal base of the cell. This Figure shows thecopper-titanium jointly drawn member 25 covered with a sheath 26, awasher 27 welded to the sheath 26, and a toric seal 28. The lower baredend 29 of the member 25 is here provided with an electrolyte leakagepurge hole 30, and terminated by a screwthread. The copper base 31 ofthe cell has apertures through which pass the exposed ends of thejointlydrawn members, and is protected by a titanium sheet 32 havingapertures with turned-down edges, corresponding to the apertures in thebase 31. The diameter of the apertures in the base is such that anannular space is provided, for positioning rings with multiple resilientcontact means 33 for making an electrical connection between theextended portions and the base of the cell which serves in thisconstruction as a general current input. The electrode extended portionis secured by clamping by means of a nut 34 which is screwed on to thescrew-threaded end of the core.

In the foregoing embodiments, it is to be understood that where atitanium component is referred to, it may be substituted with acorresponding component fashioned of another film-forming metal or alloythereof.

The terms and expressions which have been employed are used as terms ofdescription and not of limitations, and there is no intention in the useof such terms and expressions of excluding any equivalents of thefeatures shown and described or portions thereof, but it is recognizedthat various modifications are possible within the scope of theinvention claimed.

What is claimed is:

1. An electrolytic diaphragm cell comprising a plurality of verticalsubstantially flat and hollow anodes formed, as regards at least one oftheir two substantially parallel faces, by a sheet of a film-formingmetal, said anodes being secured to the base of the cell by means ofextended portions which pass through the base, characterized in that theextended portions comprise a core made of a metal which is a goodelectrical conductor, which core is covered by a sheath made of afilmforming metal, a good electrical contact being ensured between thesheath and the core, said base of the cell being of metal, which base iscovered with a sheet of film-forming metal, said core of said extendedportions is exposed where it passes through the base of said cell, theelectrical connection is made by means of metal parts arranged betweensaid core and said base and resting resiliently against said core andsaid base.

2. An electrolytic diaphragm cell accordding to claim 1, wherein saidanode rests on said base by means of an appended washer resting on atoric seal.

3. An electrolytic diaphragm cell according to claim 1, wherein saidextended portion is provided with a channel communicating with the topof said base and a point of discharge below said base.

4. An electrolytic diaphragm cell according to claim 1, wherein saidsheet of film-forming metal covering said metal base is welded to awasher-shaped member, attached to said sheath, at raised portions toeffect a seal.

1. AN ELECTROLYTIC DIAPHRAG CELL COMPRISING A PLURALITY OF VERTICALSUBSTANTIALLY FLAT AND HOLLOW ANODES FORMED, AS REGARDS AT LEAST ONE OFTHEIR TWO SUBSTANTIALLY PARALLEL FACES, BY A SHEET OF FILM-FORMINGMETAL, SAID ANODES BEING SECURED TO THE BASE OF THE CELL BY MEANS OFEXTENDED PORTIONS WHICH PASS THROUGH THE BASE, CHARACTERIZED IN THAT THEEXTENDED PORTIONS COMPRISE A CORE MADE OF A METAL WHICH IS A GOODELECTRICAL CONDUCTOR, WHICH CORE IS COVERD BY A SHEATH MADE OF AFILMFORMING METAL, A GOOD ELECTRICAL CONTACT BEING ENSURED BETWEEN THESHEATH AND THE CORE, SAID BASE OF THE CELL BEING OF METAL, WHICH BASE ISCOVERED WITH A SHEET OF FILM-FORMING METAL, SAID CORE OF SAID EXTENDEDPORTIONS IS EXPOSED WHERE IT PASSES THROUGH THE BASE OF SAID CELL, THEELECTRICAL CONNECTION IS MADE BY MEANS OF METAL PARTS ARRANGED BETWEENSAID CORE AND SAID BASE AND RESTING RESILIENTLY AGAINST SAID CORE ANDSAID BASE.
 2. An electrolytic diaphragm cell accordding to claim 1,wherein said anode rests on said base by means of an appended washerresting on a toric seal.
 3. AN ELECTROLYTIC DIAPHRAGM CELL ACCORDING TOCLAIM 1, WHEREIN SAID EXTENDED POTION IS PROVIDED WITH A CHANNELCOMMUNICATING WITH THE TOP OF SAID BASE AND A POINT OF DISCHARGE BELOWSAID BASE.
 4. An electrolytic diaphragm cell according to claim 1,wherein said sheet of film-forming metal covering said metal base iswelded to a washer-shaped member, attached to said sheath, at raisedportions to effect a seal.